First Measurements of Carbonaceous Aerosol across Urban, Rural and Residential Areas in Jeddah City, Saudi Arabia

Iqbal M. Ismail,Ahmad S. Summan,Jalal M. Basahi,Essam Hammam,Mohamed F. Yassin,Ibrahim A. Hassan 한국대기환경학회 2021 Asian Journal of Atmospheric Environment (AJAE) Vol.15 No.2

Concentrations of black carbon (BC), organic carbon (OC), and total suspended particulate matter (TSP) were simultaneously assessed in urban, rural and residential areas in Jeddah city for one year from January to December 2017. It was aimed in the present study to provide information about the spatial and seasonal variability of these aerosol species in Jeddah, and insight into sources, processes and effects of meteorological conditions. To the best of our knowledge, this is the first study investigating the variability of carbonaceous aerosols (OC and BC) in Saudi Arabia. The average concentrations of OC, BC, and TSP varied spatially and temporally. The annual average concentrations of OC, BC, and TSP were 134.05, 7.16, and 569.41 μg m-3 and 34.32, 5.14, and 240.64 μg m-3 and 10.67, 4.39 and 101.31 μg m-3 in the urban, residential and rural areas, respectively. Moreover, there was a clear seasonal variation in the concentration of carbonaceous aerosols; the highest concentrations were recorded in February and September, while the lowest concentrations of OC were recorded during April, May and August in the urban, residential and rural sites, respectively. Nevertheless, the lowest concentrations of BC were recorded during March in the urban and residential sites and during November in the rural site. The relative concentrations of OC and BC to the TSP were relatively high, and they have a significant correlation with prevalent wind speed (-0.636, and -0.581 in the urban area), (-0.539 and -0.511 in the residential area), and (-0.508 and -0.501 in the rural area), respectively. The marked differences in the concentrations of BC and OC were reflected on OC/BC ratio, which is a good representative of different source types. This preliminary study showed that the potential local sources were emissions from traffic (fossil fuel), biomass burning, anthropogenic activities (e.g. car drifting and outdoor cooking), and industrial activities. The present study suggest the presence of highly inefficient combustion sources and highlight the need for the regulation of such emissions.

Crash analysis of military aircraft on nuclear containment

M.R. Sadique,M.A. Iqbal,P. Bhargava 국제구조공학회 2015 Structural Engineering and Mechanics, An Int'l Jou Vol.53 No.1

In case of aircraft impact on nuclear containment structures, the initial kinetic energy of theaircraft is transferred and absorbed by the outer containment, may causing either complete or partial failureof containment structure. In the present study safety analysis of BWR Mark III type containment has beenperformed. The total height of containment is 67 m. It has a circular wall with monolithic dome of 21mdiameter. Crash analysis has been performed for fighter jet Phantom F4. A normal hit at the crown ofcontainment dome has been considered. Numerical simulations have been carried out using finite elementcode ABAQUS/Explicit. Concrete Damage Plasticity model have been incorporated to simulate thebehaviour of concrete at high strain rate, while Johnson-Cook elasto-visco model of ductile metals havebeen used for steel reinforcement. Maximum deformation in the containment building has reported as 33.35mm against crash of Phantom F4. Deformations in concrete and reinforcements have been localised to theimpact region. Moreover, no significant global damage has been observed in structure. It may be concludedfrom the present study that at higher velocity of aircraft perforation of the structure may happen.

Crash analysis of military aircraft on nuclear containment

Sadique, M.R.,Iqbal, M.A.,Bhargava, P. Techno-Press 2015 Structural Engineering and Mechanics, An Int'l Jou Vol.53 No.1

In case of aircraft impact on nuclear containment structures, the initial kinetic energy of the aircraft is transferred and absorbed by the outer containment, may causing either complete or partial failure of containment structure. In the present study safety analysis of BWR Mark III type containment has been performed. The total height of containment is 67 m. It has a circular wall with monolithic dome of 21m diameter. Crash analysis has been performed for fighter jet Phantom F4. A normal hit at the crown of containment dome has been considered. Numerical simulations have been carried out using finite element code ABAQUS/Explicit. Concrete Damage Plasticity model have been incorporated to simulate the behaviour of concrete at high strain rate, while Johnson-Cook elasto-visco model of ductile metals have been used for steel reinforcement. Maximum deformation in the containment building has reported as 33.35 mm against crash of Phantom F4. Deformations in concrete and reinforcements have been localised to the impact region. Moreover, no significant global damage has been observed in structure. It may be concluded from the present study that at higher velocity of aircraft perforation of the structure may happen.

Preparation of superparamagnetic maghemite (γ-Fe2O3) nanoparticles by wet chemical route and investigation of their magnetic and dielectric properties

Kashif Ali,A.K. Sarfraz,Imran M. Mirza,A. Bahadur,S. Iqbal,A. ul Haq 한국물리학회 2015 Current Applied Physics Vol.15 No.8

Maghemite (γ-Fe2O3) nanoparticles have been synthesized using a wet chemical route, optimizing the reaction time, PH value and size of the crystallite during synthesis. The Powder X-ray diffraction (XRD) measurements confirmed the presence of an impurity free maghemite phase in our sample with an average crystallite size of 16 nm as calculated from the DebyeeScherrer equation. In physical characterization, the room temperature hysteresis (M-H loop) and blocking temperature (as observed from the M-T plot) revealed that the particles are in the superparamagnetic phase at room temperature. Dielectric behaviour of γ-Fe2O3 with respect to the variation of frequency and temperature was also performed. At room temperatures, we observe a decaying behaviour of both dielectric constant (έ) and tangent looses (tanδ) at smaller frequencies while at higher frequencies both saturate to smaller constant values. In temperature dependent dielectric properties we notice that the dielectric constant (both real and imaginary parts) show an increasing trend with increasing temperatures but an overall slower enhancement at elevated frequencies. The former effect can be attributed to the possible delocalization of impurities at higher temperatures while the latter effect can be explained as an inability of the electric dipole moments to respond at higher frequencies.

Characterization and mechanism of the adsorptive removal of 2,4,6-trichlorophenol by biochar prepared from sugarcane baggase

S. Mubarik,A. Saeed,M.M. Athar,M. Iqbal 한국공업화학회 2016 Journal of Industrial and Engineering Chemistry Vol.33 No.-

Biochar from sugarcane baggase was prepared by heating at high temperature for 20 min. Surfaceproperties of the biochar were determined by Boehm titrations and FTIR. Biochar has 50.47% fixed carbonhaving methylene blue surface area of 361.77 m2/g. SEM image revealed that biochar has cylindrical,well shaped porous structures that increase surface area for adsorption. Operational parameters for2,4,6-TCP adsorption were optimized. The experimental qmax was found to be 253.38 mg/g. Biocharremoved 2,4,6-TCP in the presence of multiple pollutants. The functional moieties present on biocharshowed their affinity for 2,4,6-TCP 6¼ methylene blue > phenol > mercury.

Optimization of a laser plasma x-ray source for ultrafast x-ray absorption spectroscopy

Iqbal, M.,Ijaz, M.,Noh, D. Y.,Janulewicz, K. A.,Stiel, H.,Nickles, P. V. 한국물리학회 2017 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol. No.

<P>We present optimization of laser plasma x-ray experimental conditions for ultrafast x-ray absorption spectroscopy measurements on broad range of transition metal oxides. First, the x-ray flux generated from a laser plasma source was optimized with an emphasis on the Bremsstrahlung by investigating the influence of the angle of the incidence of laser beam on a Cu tape target. The x-ray flux emitted in both the front and transmitted side of the target was found to be optimal at the incident angle of 15 similar to 25 degrees. Moreover the manipulation of the Bremsstrahlung peak energy by the laser focus distribution was discussed. In addition to the source optimization, we present a scheme to find the time-delay zero position in a pump-probe experiment together with a normalization scheme for x-ray source fluctuations. As a feasibility check, we present the transmitted spectra of two materials, Ni and NiO.</P>

A novel high performance configuration of electrochemical cell to produce alkali for sequestration of carbon dioxide

Mehmood, A.,Iqbal, M.I.,Lee, J.Y.,Hwang, J.,Jung, K.D.,Ha, H.Y. Pergamon Press 2016 ELECTROCHIMICA ACTA Vol.219 No.-

We propose a new configuration of a 3-compartment electrochemical cell for producing alkali that is subsequently utilized for mineralization of carbon dioxide. In this new membrane configuration, a second cation exchange membrane (CEM) replaces the anion exchange membrane (AEM) employed in a standard cell configuration. The electrochemical cell comprising of two cation exchange membranes (a CEM-CEM system) eliminates the issues associated with the AEM such as low ionic conductivity and inferior mechanical strength. All of tested CEM-CEM combinations exhibit superior electrochemical performance with considerable reduction of energy requirement for NaOH production in comparison to the standard AEM-CEM configuration. The optimized two-CEMs-based system presents a remarkable enhancement of output current density by 2.5-fold and a substantial input energy savings up to 740kWhton<SUP>-1</SUP> for mineralization of carbon dioxide to produce sodium carbonate.

Generation of sub-ppb level vapor phase mixtures of biogenic volatile organic compounds from liquid phase standards and stepwise characterization of their volatilization properties by thermal desorption-gas chromatography-mass spectrometry

Iqbal, M.A.,Kim, K.H. Elsevier 2014 Journal of chromatography Vol.1373 No.-

In the analysis of biogenic volatile organic compounds (BVOCs) in ambient air, preparation of a sub-ppb level standard is an important factor. This task is very challenging as most BVOCs (e.g., monoterpenes) are highly volatile and reactive in nature. As a means to produce sub-ppb gaseous standards for BVOCs, we investigated the dynamic headspace (HS) extraction technique through which their vapors are generated from a liquid standard (mixture of 10 BVOCs: (1) α-pinene, (2) β-pinene, (3) 3-carene, (4) myrcene, (5) α-phellandrene, (6) α-terpinene, (7) R-limonene, (8) γ-terpinene, (9) p-cymene, and (10) Camphene) spiked into a chamber-style impinger. The quantification of BVOCs was made by collection on multiple-bed sorbent tubes (STs) and subsequent analysis by thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS). Using this approach, sub-ppb level mixtures of gaseous BVOCs were generated at different sweep cycles. The mean concentrations of 10 BVOCs generated from the most stable conditions (i.e., in the third sweep cycle) varied in the range of 0.37+/-0.05 to 7.27+/-0.86ppb depending on the initial concentration of liquid standard spiked into the system. The reproducibility of the gaseous BVOCs generated as mixture standards, if expressed in terms of relative standard error using the concentration datasets acquired under stable conditions, ranged from 1.64 (α-phellandrene) to 9.67% (R-limonene).

A STUDY ON ESTIMATION OF HERITABILITY OF BIRTH WEIGHT AND WEANING WEIGHT OF TEDDY GOATS KEPT UNDER PAKISTANI CONDITIONS

Tahir, M.,Younas, M.,Raza, S.H.,Lateef, M.,Iqbal, A.,Raza, P.N. Asian Australasian Association of Animal Productio 1995 Animal Bioscience Vol.8 No.6

The mean birth weight and weaning weight estimated from 777 kids from 30 bucks of Teddy goats were $1.67{\pm}0.31$ and $8.50{\pm}2.18kg$, respectively. The estimates of heritability of birth weight and weaning weight by half sib correlation method were $0.048{\pm}0.022$ and $0.101{\pm}0.012kg$, respectively. The high heritability estimates of birth weight indicates that selection on the basis of individual's own record will be effective. The low estimates of heritability of weaning weight indicates more emphasis should be given to improve environmental conditions for better achievement.

Enhancement of the electrical properties of carbon nanotubes with AreN2 plasma treatment

M. Abrar,G.U. Farwa,S. Naseer,A. Saeed,A.W. Khan,Z. Iqbal,S. T. Hussain,M. Zakaullah 한국물리학회 2013 Current Applied Physics Vol.13 No.3

Optical emission spectroscopy and Langmuir probe are used to investigate the low pressure inductively coupled AreN2 plasmas as function of rf power, filling pressure and Ar content in N2 discharge. It is observed that the active species generation, dissociation fraction and electron temperature significantly depends on discharge parameters and may be used to optimize the plasma reactor. Mixture of SWCNTs and MWCNTs are treated for different treatment time (0e120 min) at optimum discharge conditions. Changes induced in the elemental composition, surface morphology, crystallographic structure, and structural disorder in the plasma irradiated CNTs are analyzed by EDX, FTIR, SEM, XRD and Raman spectroscopy, respectively. AreN2 mixture plasma treatment of CNTs lead to a significant increase in the electrical conductivity, modify the microstructure and induce structural disorder and cause a transition of crystalline phase from well crystalline to an amorphous structure.